Production of printing plates



July 10, 1956 P. PAWLYK ETAL PRODUCTION OF PRINTING PLATES 3 Sheets-Sheet 1 Filed March 24, 1952 INVENTOR PETER PAWLYK HE R-MAN R. NACK JMI.

ATTORNEYS y 1956 P. PAWLYK ET AL 2,753,800

PRODUCTION OF 7 PRINTING PLATES Filed March 24, 1952 3 Sheets-Sheet 2 MOLD HAVING INDICIA PAP ER-MACHE MOLD (TEMPERATURE HAVING INDICIA 200F MINIMUM) (TEMPERATURE=200-300F) ExPOsE HEATED MOLD ExPosE. HEATED MOLD TO GASEOUS NICKEL TO GASEOUS NICKEL BEARING COMPOUND BEARING COMPOUND STRIP DEPOsITED sOAK PLATED MOLD NICKEL PLATE FROM [N H2O MOLD SURFACE STRIP DEPOSITED APPLY A BACK'NG NICKEL PLATE FROM TO NICKEL PLATE MOLD SURFACE PRINTING PLATE HAVING APPLY A TYPE METAL SHARPLY DEFINED BACKING TO NICKEL INDICIA 0F NICKEL PLATE FIG PRINTIN PLATE HAVING SHARPLY DEFINED 4 INDICIA OF NICKEL INvENTOR PE TER PAWLYK HERMAN R. NACK BYZ Z MLA W AT ORNEYS July 10, 1956 P. PAWLYK ET AL 2,753,800

I PRODUCTION OF PRINTING PLATES Filed March 24, 1952 3 Sheets-Sheet 5 LEAD MOLD HAVING PLASTIC MOLD HAVING INDICIA (TEMPERATURE= INDICIA (TEMPERATURE 200F- 400F) 200F TO BELOW SOFTENING POINT ExPosE MOLD TO GASEOUS NICKEL EXPOSE LD O BEARING COMPOUND GASEOUS NICKEL BEARING COMPOUND STRIP DEPOSITED I NICKEL PLATE FROM STRIP DEPOSITED LEAD MOLD NICKEL PLATE FROM PLASTIC MOLD APPLY A TYPE METAL BACKING TO APPLY A TYPE METAL NICKEL PLATE BACKING TD NICKEI. PLATE PRINTING PLATE HAVING SHARPLY PRINTING PLATEY DEFINED INDICIA HAVING SHARPLY OF NICKEL DEFINED INDICIA OF NICKEL FIG-5 FIG-6 INVENTORS PETER PAWLYK HERMAN R. NACK ATTORNEYS PnonUcTroN or PRINTING PLATES Peter Pawlyk, Dayton, and Herman R. Nack, Troy, Ohio, assignors to The Commonwealth Engineering Company of Ohio, Dayton, Ohio, a corporation of Ohio Application March 24, H52, Serial No. 278,186

12 Claims. (Cl. 101401.1)

This invention relates to printing plates and to a method of producing the same. More particularly the invention relates to printing plates of high quality having sharply defined contact surfaces.

It is customary in one method of the art to produce printing plates by first forming a mold of the page of printing which is to be reproduced, the mold being formed of papier-mache or plastic. The mold bears the printing in reverse and to form the printing plate the mold is first thoroughly cleaned and then activated with a solution such as tin chloride the excess of which is then rinsed free of the mold. Thereafter the mold surface has applied to it by spraying a light silver cost upon which there is thereafter electrolytically deposited a nickel plate of approximately .001 to .003 inch in thickness. The nickel coat is then copper plated and thereafter the combination of copper, nickel and silver plate is stripped from the matte of papier-mache or plastic. The contact surface of the electrolytically deposited film is the surface which was formed in contact with the mold and accordingly is a positive reproduction of the origins; The back of this electrolytically deposited film is, after stripping, tinned and then backed with a type metal. The contact surface may if desired be provided with a chromium plate which enhances the wear resistance of the plate.

In some instances the mold of the prior art may consist of lead but such is generally considered undesirable due to the weight of the material and the necessity for frequent handling.

It should be noted that in each of the above cases a large number of steps is required in order to procure electrotype plates.

In an alternative process adapted to higher production speeds the electro type plates may be formed by pouring into the papier-mache mold molten lead which when set is stripped from the matte backing and utilized in the printing process. While adapted for high speed production such a process, due to the inability of lead to form very sharp configurations, is inadequate where very high quality printing is required. Further such plates are of course difficult to handle due to their weight, and also lead is relatively soft and does not possess great wearing qualities.

It is a primary object of the invention to provide an improved printing plate of high quality consisting substantially only of nickel and a backing material.

It is a principal object of the invention to provide an improved process for the production of printing plates of high quality in which the number of process steps is materially reduced over that required in other processes for the production of high quality plates.

These and other allied objectives of the invention are attained by subjecting the mold of the page to be printed to a temperature of at least about 200 F. and then exposing the heated mold to an atmosphere of a nickel bearing gaseous compound which decomposes upon contact with the mold surface to deposit a metal film thereon.

[ nited States Patent 2,753,800 Patented July 10, 19 56 The thickness of the deposited metal film may be readily controlled and is preferably in the range of about 0.001 of an inch to 0.005 of an inch, the control preferably being exerted through control of the volume of carrier gas supplied per unit of time to the mold.

In the preferred embodiment the apparatus containing the mold workpiece is provided with spaced ports through which the gaseous compound enters, the ports being so located as to provide a uniform metallic deposit over the exposed mold surface. The metal deposits from the vapor in very fine particles and enters the smallest of recesses in the mold surface and the deposited film is of such a structure as to retain its form when the film is removed from the mold after completion of the plating operation.

Release of the metal film from the mold in the case of papier-mache may be effected by soaking the same in water or in water containing a wetting agent, and in the alternative the papier-mache may first be treated with a silicone solution to aid the release of the metal film. Normally plastic surfaces will not require a mold release agent and metal films may be removed therefrom directly, and this is also the case where the mold material is of lead, although in given instances mold release agents known to the art may be used as required. a

The surface of the nickel film which bore against the mold surface may have a light film of chromium applied thereto in order to improve the wear resistant qualities of the plate. To the other sideof the film a backing, for example of type metal, may be applied in order that the completed plate may withstand the pressures to which it is subjected when in use.

Summarizing the invention, the product of invention consists of a film of nickel accurately formed to the contour of the mold from which it is produced, the metal film being backed with a thickness of a strengthening material to permit it to withstand the pressures applied in the printing processes.

The inventive process consists in the deposition of metal from the gaseous state upon mould sections having sharply diverging lines or printing characters such as are found on printing blocks and the formation of a of sufficient coherency to withstand the applied pressures in the use of the film when combined with a metal backing material.

The invention will be more fully understood by reference to the following description and detailed examples and figures of the drawings wherein:

Figure 1 illustrates schematically apparatus useful in the production of the plate of invention;

Figure 2 is an elevational view of the plate ofinv'ention;

Figure 3 is a flow chart indicating the steps of the process of invention; and

Figures 4, 5 and 6 are flow charts indicating the steps in the specific embodiment of the invention.

There is shown in Figure 1 at 1 a tank of inert carrier gas such as carbon dioxide which tank is provided with a valve 2 and a fiowmeter 3 in line 4 which passes from the tank 1 to a carburetor 5 immersed in oil 6 contained in tank 7 which oil and carburetor are maintained at a constant temperature by means of heater 8 and the thermostat unit indicated generally at 10.

Tank 7 is provided with a stirrer 12 driven by a motor 14 through belting 16. To the upper end of the carburetor 5 there is secured a line 18 which passes through pump 20 to a chamber 22 in which there is secured a metal plate 24 insulated from the walls by support members 25. Extending into the chamber is a conduit portion 26 having therein apertures 28 facing member 24. Surrounding the chamber 22' is a water jacket 30 provided with an inlet port 32 and an outlet port 34. Adjacent the water jacket 30 and outside of the chamber 22 is an inductive heat source in the form of a coil 36 electrically connected with a power supply (not shown).

The remote end of the chamber 22 is provided with a removable cover 38 for the insertion of specimens to be plated upon the plate 24. This cover is provided with an aperture through which extends a conduit 40 and which terminates in a trap 42 surrounded by cooling Water 44 flowing through tank 46 through inlet 48 and outlet 50.

In carrying out the process of invention the carrier gas, for instance carbon dioxide, is bled from the tank 1 through the carburetor 5 where the nickel bearing compound is vaporized and entrained and carried to the plating chamber.- The plating gas issuing from the apertures 28 in the conduit extension 26 deposits on the mold, as for example a papier-mache, which is heated directly by its contact with plate 24, the plate itself being heated by means of current applied to the induction coil.

Gases which are not decomposed and those gases which are decomposed pass out through the remote end of the chamber to the trap 42 wherein the metal components are cooled and deposited, while the vapor portion including carbon dioxide formed pass out to the atmosphere.

The following examples set forth in detail the conditions under which a nickel plating having an extremely sharp configuration and conforming substantially identical to the configuration of the mold, whether the same be a papier-mache, plastic or lead, may be produced.

Example 1 Mold of papier-mache Temperature 260 F. Carburetor temperature 50 F. Rate of carrier gas flow 0.5 liter per minute. Rate of metal depositionruu .0002 inch per minute. Thickness of plate .001 of an inch. Plating time Approximately 5 minutes. Plating gas Nickel carbonyl and carbon dioxide carrier. Mold size 4" x 4'.

Example 11 Mold or papier-mache Temperature 280 F. Carburetor temperature 70 F. Carrier gas Carbon dioxide. Rate of carrier gas flow 20 liter per minute. Rate of metal deposition .0015 inch per minute. Thickness of plate .005 of an inch. Plating time Approximately 3 minutes. Plating gas Nickel carbonyl and carbon dioxide carrier. Mold size 4" x 4".

Example 111 Plastic mold Temperature 200 F. Carburetor temperature 100 F. Rate of carrier gas flow 20 liters per minute. Rate of metal deposition"--- .0010 inch per minute. Thickness of plate .005 of an inch. Plating time Approximately 5 minutes. Plating gas Nickel carbonyl and carbon dioxide carrier. Mold size 4" x 4".

Example IV Lead mold Temperature 350 F. Carburetor temperature 75 F. Rate of carrier gas flow 15 liters per minute. Rate of metal deposition--- .0010 inch per minute. Thickness of plate .005 of an inch. Plating time Approximately 5 minutes. Plating gas Nickel carbonyl and carbon dioxide carrier. Mold size 4" x 4".

It will be noted in connection with each of the foregoing examples that as is usual in the art the plating chamber is cleared of oxygen and other gases prior to the raising of the workpiece to the plating temperature by simply passing a flow of carbon dioxide through the chamber or a flow of plating gas through the chamber.

It may be noted in connection with the foregoing that insulating lines are used in the equipment and hence the length of a line plays substantially no part in the operating conditions, the temperature at the carburetor being substantially the same as the temperature at the point of plating.

It should also be noted that it is not desirable to use too high a rate of flow of the metal bearing material in the production of small thicknesses as too much loss of plating material is rendered thereby. Also it is not advisable to use too low a flow rate with the high thickness since then an excessive plating time is required. We have found that it is preferably to match the flow rates against the required thickness in such fashion that a uniform deposition rate is obtained and in the thickness ranges indicated a plating time of about 3 to 5 minutes has been found extremely desirable for the production of coherent nickel deposits.

Under these conditions the coherent nickel plate strips readily from the mold, the contact surface having raised and recessed impressions which are true replicas of the mold surface.

The nickel plates secured by following the procedure in each of the examples set forth hereinbefore may be tinned on the reverse side and backed with a heavier metal, for example a type metal, in order that the metal plate may withstand the pressures applied in the course of the use of the film.

It is also noted as hereinbefore set forth that the contact face of the plate may be provided with a thin layer of chromium in order to increase its wear resistant qualities. Since the ranges set forth in the specific examples are considered to be optimum conditions it should be noted that where the mold is of papier-mache the temperature of the mold may be suitably between 200 and 300 F. and where of lead between 200 and 400 F., while the plastic molds may be subjected to temperatures of from about 200 F. to just below their distortion temperature. The carburetor temperatures which are useful may vary from 32 to 104 F. with the carrier gas flow rate of 0.5 liters per minute to 20 liters per minute.

It will be noted that in each case the mold should be heated to at least 200 F. and the temperature should always be below the distortion point of the material used.

The flow rates and the plating rates are not critical, but as indicated in the examples may be between about 5 liters per minutes and from about .002 inch to .0015 inch per minute, respectively.

Plastics from which molds may be suitably prepared include thermosetting resins, such as the phenol formaldehydes and urea melamines, as well as the thermoplastics including the vinyls such as vinyl chloride and vinyl acetate; but the invention is considered to be suitable for any plastic material which will withstand at least 200 F. temperature without distortion and is considered to be suitable in the process of invention.

The depth of the impression in the mold surface has no critical limit so far as is presently known it being necessary only to provide sufiicient deposit of nickel to fill the impression and attain in addition a thickness of .001 to .005 of an inch in the body of the nickel plate. Normally however with deep impressions it is advisable to apply a heavy body, that is .005 of an inch thick in order to body the product uniformly.

The impressions on the nickel plate are exceedingly sharp for recessed as well as the raised indicia as the metal deposited from the vapor state apparently clings compactly to the mold surface which it strikes whether the mold impression be upraised or recessed.

The nature of the plastics useful in the molds required mason for the inventive process is not critical the only requirement being that the material does not soften at the minimum temperature of 200 F. required in the process for decomposition of the nickel carbonyl.

The gas pressure within the plating chamber may vary over a wide range from slightly above atmospheric to pressures as low as 40 mm. of mercury. At the lower pressures considerable precaution should be taken to prevent leakage of air into the system as the presence of oxygen would tend to affect the coherency of the deposited coat deleteriously.

It will be understood that While there have been given herein certain specific examples of the practice of this invention, it is not intended thereby to have this invention limited to or circumscribed by the specific details herein specified, in view of the fact that this invention may be modified according to individual preference or conditions without necessarily departing from the spirit of this disclosure and the scopeof the appended claims.

We claim:

1. In a method of producing a printing plate the steps comprising positioning a mold having printing characters thereon within an enclosed spacing, clearing the spacing of gases, heating the mold surface to at least 200 F., contacting the said heated surface with a vapor containing a nickel carbonyl whereby the said carbonyl is decomposed depositing a thin film of nickel compactly over the mold surface and over the printing characters on the mold surface to form sharp configurations of the printing characters, removing the mold from the enclosed spacing, and releasing the deposited film of nickel from the mold.

2. In a method of producing a printing plate the steps comprising positioning a mold having printing characters thereon Within an enclosed spacing, clearing the spacing of gases, heating the mold surface to at least 200 F., contacting the said heated surface with a heated vapor containing a nickel carbonyl whereby the said carbonyl is decomposed depositing a thin film of nickel compactly over the mold surface and over the printing characters on the mold surface to form sharp configurations of the printing characters, removing the mold from the enclosed spacing, and releasing the deposited film of nickel from the mold.

3. In a method of producing a printing plate the steps comprising positioning a mold having printing characters thereon within an enclosed spacing, clearing the spacing of gases, heating the mold surface of papier-mache to at least 200 F., contacting the said heated surface with a vapor containing a nickel carbonyl whereby the said carbonyl is decomposed depositing a thin film of nickel compactly over the mold surface and over the printing characters on the mold surface to form sharp configurations of the printing characters, removing the mold from the enclosed spacing, and releasing the deposited film of nickel from the mold.

4. In a method of producing a printing plate the steps comprising positioning a mold having printing characters thereon Within an enclosed spacing, clearing the spacing of gases, heating the mold surface of plastic to at least 200 F., contacting the said heated surface with a vapor containing a nickel carbonyl whereby the said carbonyl is decomposed depositing a thin film of nickel compactly over the mold surface and over the printing characters on the mold surface to form sharp configurations of the printing characters, removing the mold from the enclosed spacing, and releasing the deposited film of nickel from the mold.

5. In a method of producing a printing plate the steps comprising positioning a mold having printing characters thereon Within an enclosed spacing, clearing the spacing of gases, heating the mold surface of lead to at least 200 F., and contacting the said heated surface with a vapor containing a nickel carbonyl whereby the said carbonyl is decomposed depositing a thin film of 6 nickel compactly over the mold surface and over the printing characters on the mold surface to form sharp configurations of the printing characters, removing the mold from the enclosed spacing, and releasing the deposited film of nickel from the mold.

6. In a method of producing a printing plate the steps comprising positioning a mold having printing'characters thereon within an enclosed spacing, clearing the spacing of gases, heating the mold surface to at least 200 F., and directing a vapor containing a concentration of nickel carbonyl onto the heated surface at a flow rate sufficient to deposit a nickel film of .001 to .005 inch thickness in three to five minutes, the nickel film being deposited uniformly over the characters on the mold surface to form sharp configurations thereof, removing the mold from the spacing, and releasing the deposited film of nickel from the mold.

7. In a method of producing a printing plate the steps comprising positioning a mold having printing characters thereon Within an enclosed spacing, clearing the spacing of gases, heating the mold surface to at least 200 F., and directing a vapor containing a carrier gas and a concentration of nickel carbonyl onto the heated surface at a flow rate sufiicient to deposit a nickel film of .001 to .005 inch thickness in three to five minutes, the nickel film being deposited uniformly over the characters on the mold surface to form sharp configurations thereof, removing the mold from the spacing, and releasing the deposited film of nickel from the mold.

8. In a method of producing a printing plate the steps of positioning a mold having printing characters thereon within an enclosed spacing, clearing the spacing of gases, heating the mold surface of papier-mache to about 260 F., passing carbon dioxide carrier gas at a flow rate of about 0.5 liters per minute through a carburetor at a temperature of 50 F. to vaporize nickel carbonyl contained therein, thereby entraining nickel carbonyl vapors in the carrier gas, and directing the gases onto the heated mold surface at a flow rate sufficient to deposit a nickel film .001 inch thick in about five minutes, the nickel film being deposited uniformly over the char acters on the mold surface to form sharp configurations thereof, removing the mold from the spacing, and releasing the deposited film of nickel from the mold.

9. In a method of producing a printing plate the steps of positioning a mold having printing characters thereon within an enclosed spacing, clearing the spacing of gases, heating the mold surface of papier-mache to about 280 F., passing carbon dioxide carrier gas at a flow rate of about 20 liters per minute through a carburetor at a temperature of 70 F. to vaporize nickel carbonyl contained therein, thereby entraining nickel carbonyl vapors in the carrier gas, and directing the gases onto the heated mold surface at a flow rate sufficient to deposit a nickel film having a thickness of about .005 inch in about three minutes, the nickel film being deposited uniformly over the characters on the mold surface to form sharp configurations thereof, removing the mold from the spacing, andreleasing the deposited film of nickel from the mold.

10. In a method of producing a printing plate the steps of positioning a mold having printing characters thereon Within an enclosed. spacing, clearing the spacing of gases, heating the mold surface of plastic to at least 200 F., passing carbon dioxide carrier gas at a flow rate of about 20 liters per minute through a carburetor at a temperature of F. to vaporize nickel carbonyl contained therein, thereby entraining nickel carbonyl vapors in the carrier gas, and directing the gases onto the heated mold surface at a How rate suficient to deposit a nickel film having a thickness of about .005 of an inch in about five minutes, the nickel film being deposited uniformly over the characters on the mold surface to form sharp configurations thereof, removing the mold from the spacing, and releasing the deposited film of nickel from the mold.

11. In a method of producing a printing plate the steps of positioning a mold having printing characters thereon Within an enclosed spacing, clearing the spacing of gases, heating the mold surface of lead to about 350 F., passing carbon dioxide carrier gas at a flow rate of about 15 liters per minute through a carburetor at a temperature of 75 F. to vaporize nickel carbonyl contained therein, thereby entraining nickel carbonyl vapors in the carrier gas, and directing the gases onto the heated mold surface at a flow rate sufiicient to deposit a nickel film having a thickness of about .005 of an inch in about five minutes, the nickel film being deposited uniformly over the characters on the mold surface to form sharp configurations thereof, removing the mold from the spacing, and releasing the deposited film of nickel from the mold.

12. As an article of manufacture, a printing plate made in accordance With the process of claim 11.

References Cited in the file of this patent UNITED STATES PATENTS 1,680,097 Eaton Aug. 7, 1928 1,803,548 Drake May 5, 1931 1,978,791 Hale Oct. 30, 1934 8 2,074,281 Sommer Mar. 16, 1937 2,148,045 Burkhardt et al. Feb. 21, 1939 2,153,786 Alexander et al. Apr. 11, 1939 2,157,478 Burkhardt et a1 May 9, 1939 2,214,950 Aller Sept. 17, 1940 2,248,275 Lengel July 8, 1941 2,304,182 Lang Dec. 8, 1942 2,344,138 Drummond Mar. 14, 1944 2,475,601 Fink July 12, 1949 2,523,461 Young et al. Sept. 26, 1950 2,576,289 Fink Nov. 27, 1951 2,580,976 Toulmin Jan. 1, 1952 2,619,433 Davis et al. Nov. 25, 1952 2,685,124 Toulmin Aug. 3, 1954 OTHER REFERENCES Hackleman: Commercial Engraving and Printing, 1921, Commercial Engraving Publishing Co., Indianapolis. Copy available in Div. 17. Only pp. 352 to 354 and 362 cited.

Barber: Photo-Engraving, Electrotyping and Stereotyping. Vol. IV of the Art and Practice of Printing, 1933, Pitman & Sons, Ltd., London. Only pages 260 to 266 made of record. Copy available in Division 17.. 

1. IN A METHOD OF PRODUCING A PRINTING PLATE THE STEPS COMPRISING POSITIONING A MOLD HAVING PRINTING CHARACTERS THEREON WITHIN AN ENCLOSED SPACING, CLEARING THE SPACING OF GASES, HEATING THE MOLD SURFACE TO AT LEAST 200* F., CONTACTING THE SAID HEATED SURFACE WITH A VAPOR CONTAINING A NICKEL CARBONYL WHEREBY THE SAID CARBONYL IS DECOMPOSED DEPOSITING A THIN FILM OF NICKEL COMPACTLY OVER THE MOLD SURFACE AND OVER THE PRINTING CHARACTERS ON THE MOLD SURFACE TO FORM SHARP CONFIGURATIONS OF THE PRINTING CHARACTERS, REMOVING THE MOLD FROM THE ENCLOSED SPACING, AND RELEASING THE DEPOSITED FILM OF NICKEL FROM THE MOLD. 